In conventional electrical machines, when the armatures or rotors are subjected to load, certain undesirable effects occur. More specifically, when current flows through the armature or rotor conductors, there is produced armature or rotor reaction flux in the air gap which changes both the magnitude and distribution of the flux crossing the air gap and adds vectorially to the main magnetic field, producing a resultant magnetic field which lies in a different direction from the main magnetic field, causing phase and wave form distortions in the main magnetic field flux.
Another undesirable effect in conventional electrical machines is the production of high frequency flux in the air gap, causing losses, heating and dielectric breakdown.
In studying these problems of the conventional electrical machines, I have found that the armature or rotor reaction flux and the high frequency flux of the air gap can be greatly reduced by the installation of a short-circuit ring winding and by providing a non-magnetic material on the armature or rotor all without necessitating substantial changes in existing equipment and in normal techniques of winding and installation of such winding.